# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
# RUN: llc -mtriple=hexagon -hexagon-mcr=true -run-pass=machine-combiner\
# RUN:  %s -o - | FileCheck %s --check-prefix=ENABLED
# RUN: llc -mtriple=hexagon -hexagon-mcr=false -run-pass=machine-combiner\
# RUN:  %s -o - | FileCheck %s --check-prefix=DISABLED

# Test that demonstrates the machine-combiner pass performing reassociation
# to improve instruction-level parallelism (ILP) by breaking dependency chains.

--- |
  define float @test_reassoc_chain(float* nocapture readonly %a) {
    ret float 0.0
  }
...

---
# Test a longer chain: ((A + B) + C) + D
# Should reassociate to optimize the critical path
# Verify we still have 3 F2_sfadd instructions but in optimized order
# Original chain should be preserved

name: test_reassoc_chain
tracksRegLiveness: true
body: |
  bb.0:
    liveins: $r0

    ; ENABLED-LABEL: name: test_reassoc_chain
    ; ENABLED: liveins: $r0
    ; ENABLED-NEXT: {{  $}}
    ; ENABLED-NEXT: [[COPY:%[0-9]+]]:intregs = COPY $r0
    ; ENABLED-NEXT: [[L2_loadri_io:%[0-9]+]]:intregs = L2_loadri_io [[COPY]], 0
    ; ENABLED-NEXT: [[L2_loadri_io1:%[0-9]+]]:intregs = L2_loadri_io [[COPY]], 4
    ; ENABLED-NEXT: [[F2_sfadd:%[0-9]+]]:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed [[L2_loadri_io1]], killed [[L2_loadri_io]], implicit $usr
    ; ENABLED-NEXT: [[L2_loadri_io2:%[0-9]+]]:intregs = L2_loadri_io [[COPY]], 8
    ; ENABLED-NEXT: [[L2_loadri_io3:%[0-9]+]]:intregs = L2_loadri_io [[COPY]], 12
    ; ENABLED-NEXT: [[F2_sfadd1:%[0-9]+]]:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed [[L2_loadri_io2]], killed [[L2_loadri_io3]], implicit $usr
    ; ENABLED-NEXT: [[F2_sfadd2:%[0-9]+]]:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed [[F2_sfadd]], killed [[F2_sfadd1]], implicit $usr
    ; ENABLED-NEXT: $r0 = COPY [[F2_sfadd2]]
    ; ENABLED-NEXT: PS_jmpret $r31, implicit-def dead $pc, implicit $r0
    ;
    ; DISABLED-LABEL: name: test_reassoc_chain
    ; DISABLED: liveins: $r0
    ; DISABLED-NEXT: {{  $}}
    ; DISABLED-NEXT: [[COPY:%[0-9]+]]:intregs = COPY $r0
    ; DISABLED-NEXT: [[L2_loadri_io:%[0-9]+]]:intregs = L2_loadri_io [[COPY]], 0
    ; DISABLED-NEXT: [[L2_loadri_io1:%[0-9]+]]:intregs = L2_loadri_io [[COPY]], 4
    ; DISABLED-NEXT: [[F2_sfadd:%[0-9]+]]:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed [[L2_loadri_io1]], killed [[L2_loadri_io]], implicit $usr
    ; DISABLED-NEXT: [[L2_loadri_io2:%[0-9]+]]:intregs = L2_loadri_io [[COPY]], 8
    ; DISABLED-NEXT: [[L2_loadri_io3:%[0-9]+]]:intregs = L2_loadri_io [[COPY]], 12
    ; DISABLED-NEXT: [[F2_sfadd1:%[0-9]+]]:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed [[L2_loadri_io2]], killed [[L2_loadri_io3]], implicit $usr
    ; DISABLED-NEXT: [[F2_sfadd2:%[0-9]+]]:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed [[F2_sfadd]], killed [[F2_sfadd1]], implicit $usr
    ; DISABLED-NEXT: $r0 = COPY [[F2_sfadd2]]
    ; DISABLED-NEXT: PS_jmpret $r31, implicit-def dead $pc, implicit $r0
    %0:intregs = COPY $r0
    %1:intregs = L2_loadri_io %0:intregs, 0
    %2:intregs = L2_loadri_io %0:intregs, 4
    %3:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed %2:intregs, killed %1:intregs, implicit $usr
    %4:intregs = L2_loadri_io %0:intregs, 8
    %5:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed %3:intregs, killed %4:intregs, implicit $usr
    %6:intregs = L2_loadri_io %0:intregs, 12
    %7:intregs = nnan ninf nsz arcp contract afn reassoc F2_sfadd killed %5:intregs, killed %6:intregs, implicit $usr
    $r0 = COPY %7:intregs
    PS_jmpret $r31, implicit-def dead $pc, implicit $r0
...